The frustrating thing about this place is the inconsistency of quality of the dishes. Some are great and others I can't believe they even put up.
Great: salmon sashimi, prime rib, lobster tail, crawfish, beef ribs.
Sucks: fish (obviously frozen and frozen badly), clams (overcooked), mussels (overcooked).
The gold standard in Vegas is the Bellagio Buffet. Unless you stay at the Rio and are too lazy to go to the Bellagio, go to the Bellagio Buffet and even save a few bucks.